I have black walnut trees in my backyard and struggle with what type of...

Asked April 1, 2014, 1:32 PM EDT

I have black walnut trees in my backyard and struggle with what type of flowers, both perennial and annual that will grow well in not only shadier areas but with the toxicity from black walnut trees. Is there someone who could help me "design" a flower garden that will work?

Redwood County Minnesota

1 Response

Thank you for the question. For starters, please note these Iowa State University recommendations: "Gardeners who have large walnut trees near their vegetable gardens should consider an alternate site. The greatest concentration of juglone in the soil exists within the dripline of the trees. The dripline is the area between the trunk of the tree and the end of the branches. The toxic zone from a mature tree occurs on average in a 50-foot radius from the trunk. Avoid planting your garden in these areas to protect your garden from damage." You may be able to grow plants sensitive to juglone (the black walnut chemical toxic to some plants) successfully near the tree by planting them in a lined (weed fabric) raised bed filled with clean soil. This assumes that the bed will not be under the tree's canopy. Do not create or use compost or mulch that contains leaves or any other parts of the black walnut tree. This web site provides an excellent list of plants known to be sensitive or insensitive to juglone: Black Walnut Toxicity http://hort.uwex.edu/articles/black-walnut-toxicity This University of Minnesota publication "The Best Plants for 30 Tough Sites" has good information on growing under black walnut and also in shade. http://www.extension.umn.edu/garden/yard-garden/landscaping/best-plants-for-tough-sites/ For design assistance, contact your local extension office and ask if they have resources for you. Here is Redwood County Extension contact information: 403 Mill St PO 130 Redwood Falls, MN 56283-0130 507-637-4025